Contact sensitization to hair colours in acquired dermal macular hyperpigmentation: results from a patch and photo-patch test study of 108 patients.

BACKGROUND: Acquired dermal macular hyperpigmentation (ADMH) is an umbrella term including lichen planus pigmentosus, erythema dyschromicum perstans and pigmented contact/cosmetic dermatitis. OBJECTIVE: To establish contact sensitization to hair colours as an aetiological factor for ADMH. METHODS: Detailed clinical examination, skin biopsies, and patch and photo-patch testing with Indian standard series and patient's own cosmetic products were performed. RESULTS: Thirty-nine (36.1%) patients were found to demonstrate a positive patch/photo-patch test with 35/39 reacting to their own products (all were hair colours) and 16/39 reacting to antigens from commercial series (commonly paraphenylenediamine). Fourteen patients developed delayed hyperpigmentation on positive patch-test sites at 1 month. Higher mean age, symptomatic pigmentation (pruritus, burning and photosensitivity), hair margins involvement (outer surface, helix and lobule of ear; temples and preauricular area), ill-defined lesions, epidermal atrophy and epidermal melanization extending >3 layers were significantly common in patch-test-positive patients. Well-defined lesions, perioral involvement and associated lichen planus were clinical pointers towards patch-test negativity. CONCLUSION: Index study exemplifies that patch-test results have distinct clinical and histopathological correlates in ADMH. Hair dye contact sensitization appears to be an important aetiological factor in about one-third patients presenting with ADMH.

Four compartment method as an efficacious and simplified technique for autologous non-cultured epidermal cell suspension preparation in vitiligo surgery: A randomized, active-controlled study.

BACKGROUND: Autologous non-cultured epidermal cell suspension (NCES) is a successful surgical method for repigmentation of stable, refractory vitiligo. The need for laboratory equipment and expertise restricts its use to only a few research centres; hence, there is a requisite to simplify the technique of NCES preparation. OBJECTIVES: To evaluate the efficacy of NCES prepared by four compartment (4C) method compared to the laboratory-based method (lab-NCES). METHODS: Anatomically based matched lesions (41 pairs) in 30 stable vitiligo patients were randomized to receive NCES prepared by 4C method or lab-NCES. Each patient was evaluated at 4, 8, 16 weeks after surgery by a blinded observer with regard to extent of repigmentation, colour match, patient global assessment (PGA) and pattern of repigmentation. RESULTS: Repigmentation outcome in 4C method as compared to lab-NCES was as follows: excellent (≥90%) repigmentation: 34% vs. 37%, P = 1.000, good (≥75%) repigmentation: 68% vs. 71%, P = 1.000; colour match: 59% vs. 54%, P = 0.794, patient satisfaction based on PGA score - 23.02 vs. 23.39 (P = 0.210) and major pattern of repigmentation (diffuse) - 76% vs. 71% (P = 0.618). LIMITATIONS: Short follow-up period of 16 weeks. CONCLUSION: Four compartment method is a simple and effective technique for vitiligo surgery in routine clinical practice.